cdc_wdm 1-1:1.0: Stall on int endpoint
cdc_wdm 1-1:1.0: Stall on int endpoint
cdc_wdm 1-1:1.0: Stall on int endpoint
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1
WARNING: kernel/rcu/tree_stall.h:1049 at rcu_check_gp_start_stall.part.0+0x1c4/0x4b0 kernel/rcu/tree_stall.h:1049, CPU#1: kworker/1:0/23
Modules linked in:
CPU: 1 UID: 0 PID: 23 Comm: kworker/1:0 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:rcu_check_gp_start_stall.part.0+0x1c4/0x4b0 kernel/rcu/tree_stall.h:1049
Code: 88 61 01 00 00 be 04 00 00 00 48 c7 c7 00 aa d9 93 e8 10 1e 7c 00 b8 01 00 00 00 87 05 c5 96 42 12 85 c0 0f 85 3d 01 00 00 90 <0f> 0b 90 48 c7 c3 74 e2 cc 8a 48 81 fd 00 64 4e 89 74 5a 48 b8 00
RSP: 0000:ffffc900001a8df8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000002904 RCX: ffffffff81971330
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff93d9aa00
RBP: ffffffff894e6400 R08: 0000000000000001 R09: fffffbfff27b3540
R10: 0000000000000003 R11: 0000000000000000 R12: 1ffffffff1242250
R13: 0000000000000246 R14: ffffffff894e6400 R15: ffff8881f5739f12
FS:  0000000000000000(0000) GS:ffff888268a6a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f47cac22000 CR3: 0000000131d8a000 CR4: 00000000003506f0
Call Trace:
 <IRQ>
 rcu_check_gp_start_stall kernel/rcu/tree_stall.h:1012 [inline]
 rcu_core+0x4e8/0x15c0 kernel/rcu/tree.c:2852
 handle_softirqs+0x1dd/0x8f0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xed/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:console_flush_one_record+0xac3/0xe50 kernel/printk/printk.c:3216
Code: 00 e8 11 59 28 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 5f 76 20 00 48 85 ed 0f 85 d7 01 00 00 e8 71 7b 20 00 fb 4c 89 e8 <48> c1 e8 03 42 80 3c 38 00 0f 85 64 03 00 00 48 8b 0c 24 48 8b 6b
RSP: 0000:ffffc9000018f310 EFLAGS: 00000246
RAX: ffffffff89a50638 RBX: ffffffff89a505e0 RCX: ffffc90010d6c000
RDX: 0000000000100000 RSI: ffffffff8190c08f RDI: ffff8881022857c0
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 000000000000672c
R13: ffffffff89a50638 R14: ffffc9000018f390 R15: dffffc0000000000
 console_flush_all kernel/printk/printk.c:3289 [inline]
 __console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
 console_unlock+0x103/0x260 kernel/printk/printk.c:3359
 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2426
 dev_vprintk_emit+0x394/0x3e0 drivers/base/core.c:4914
 dev_printk_emit+0xd2/0x10d drivers/base/core.c:4925
 __dev_printk+0xcb/0x100 drivers/base/core.c:4937
 _dev_info+0xef/0x127 drivers/base/core.c:4983
 hub_port_init.cold+0x124/0x389 drivers/usb/core/hub.c:4996
 hub_port_connect drivers/usb/core/hub.c:5496 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
 port_event drivers/usb/core/hub.c:5871 [inline]
 hub_event+0x2f27/0x4af0 drivers/usb/core/hub.c:5953
 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257
 process_scheduled_works kernel/workqueue.c:3340 [inline]
 worker_thread+0x5da/0xe40 kernel/workqueue.c:3421
 kthread+0x3b3/0x730 kernel/kthread.c:463
 ret_from_fork+0x6c3/0xa20 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
----------------
Code disassembly (best guess):
   0:	00 e8                	add    %ch,%al
   2:	11 59 28             	adc    %ebx,0x28(%rcx)
   5:	00 9c 5d 81 e5 00 02 	add    %bl,0x200e581(%rbp,%rbx,2)
   c:	00 00                	add    %al,(%rax)
   e:	31 ff                	xor    %edi,%edi
  10:	48 89 ee             	mov    %rbp,%rsi
  13:	e8 5f 76 20 00       	call   0x207677
  18:	48 85 ed             	test   %rbp,%rbp
  1b:	0f 85 d7 01 00 00    	jne    0x1f8
  21:	e8 71 7b 20 00       	call   0x207b97
  26:	fb                   	sti
  27:	4c 89 e8             	mov    %r13,%rax
* 2a:	48 c1 e8 03          	shr    $0x3,%rax <-- trapping instruction
  2e:	42 80 3c 38 00       	cmpb   $0x0,(%rax,%r15,1)
  33:	0f 85 64 03 00 00    	jne    0x39d
  39:	48 8b 0c 24          	mov    (%rsp),%rcx
  3d:	48                   	rex.W
  3e:	8b                   	.byte 0x8b
  3f:	6b                   	.byte 0x6b